Answer:
Explanation:Puesto que la energía causante de la aceleración del espacio-tiempo no ha podido ser observada en forma directa, se ha dado en llamarla energía oscura. Dos candidatos teóricos que podrían hacer las veces de esta energía son una constante cosmológica no igual a cero (que pudo haber causado la inflación cósmica) y una energía repulsiva más general llamada quintaesencia.
Pretty sure it shows a chemical reaction
<u>Answer:</u> The tendency of an element to react is closely related to the number of valence electrons in the element.
<u>Explanation:</u>
Chemical reactivity is defined as the tendency of an element to loose of gain electrons.
Metals tend to loose electrons and so their chemical reactivity is the tendency to loose electrons.
Non-metals tend to gain electrons and so their chemical reactivity is the tendency to gain electrons.
The number of electrons that an element will loose or gain depends on the number of valence electrons present around that element.
<u>For Example:</u> Chlorine has 7 valence electrons and need 1 electron to complete its octet, whereas sulfur has 6 valence electrons and need 2 electrons to complete its octet.
So, chlorine will gain 1 electron easily than sulfur and thus, is more reactive than sulfur.
Hence, the tendency of an element to react is closely related to the number of valence electrons in the element.